Tungsten-Coated Nickel Cathode Oxide for Low Capacity Leakage
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Lithium nickel-based composite oxides with tungsten (W) exhibit high capacity leakage when used in solid-state batteries, necessitating an improvement in the positive electrode active material to enhance electrochemical characteristics and reduce capacity leakage, especially at higher temperatures.
Innovation Solution
A positive electrode active material comprising Li, Ni, Co, Mn, W, Al, F, and additional elements like B, Ba, Ca, Cr, Fe, Mg, Mo, Nb, S, Si, Sr, Ti, Y, and Zr, with specific atomic ratios and compositions, optimized through ICP and IC analysis, and processed to achieve improved electrochemical stability and reduced capacity leakage.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Power
If tungsten (W) is added to lithium nickel-based composite oxide, then electrochemical activity is enhanced, but capacity leakage increases significantly
Solution Approach 1:
The patent applies local quality by creating a dual-composition structure where the particle interior maintains high Ni content (50-95 mol%) for electrochemical activity, while the particle surface contains Al and W elements forming a protective coating layer. This spatial differentiation allows the core to provide high power while the surface layer suppresses capacity leakage, resolving the contradiction between electrochemical activity and energy loss.
Solution Approach 2:
The patent employs composite materials by combining multiple elements (Li, Ni, Co, Mn, W, Al, and optional Q elements) in specific ratios to create a composite oxide structure. The synergistic interaction between these elements, particularly Al and W on the surface, enables simultaneous achievement of high electrochemical activity and reduced capacity leakage that cannot be obtained with single-element modifications.
2Power
If nickel content is increased to improve capacity, then electrochemical performance improves, but capacity leakage worsens
Solution Approach 1:
The patent implements local quality by allowing high Ni content (50-95 mol%) in the particle interior to maintain electrochemical performance, while restricting Ni at the surface and concentrating Al and W there instead. This spatial separation enables the bulk material to deliver high capacity while the surface layer prevents leakage, solving the contradiction between performance and energy loss.
Solution Approach 2:
The patent applies parameter changes by precisely controlling the atomic percentages of each element within specific ranges (Ni: 50-95 mol%, Al: 0.1-3.0 mol%, W: 0.05-2.0 mol%) and their surface-to-bulk distribution. These quantitative parameter optimizations enable the material to achieve the desired balance between high electrochemical performance and reduced capacity leakage.
3Reliability
If aluminum and tungsten are added to reduce capacity leakage, then stability improves, but manufacturing complexity increases
Solution Approach 1:
The patent applies merging by combining Al and W additions into a single surface-modification step that simultaneously achieves multiple functions: Al forms a stable oxide layer to suppress leakage, while W enhances electrochemical activity. This combined approach consolidates multiple potential processing steps into one, reducing manufacturing complexity while achieving both stability and performance improvements.
Solution Approach 2:
The patent uses parameter changes by defining specific compositional ranges (Al: 0.1-3.0 mol%, W: 0.05-2.0 mol%) that optimize both stability and manufacturability. By specifying narrow, well-defined parameter ranges, the patent simplifies quality control and manufacturing processes compared to broader, less-defined compositions, thereby improving reliability without excessively increasing complexity.
Data Source
AI summary
The present invention relates to a lithium nickel-based composite oxide as a positive electrode active material for lithium-ion rechargeable batteries suitable for electric vehicle and hybrid electric vehicle applications, comprising lithium nickel-based oxide particles comprising tungsten.